Aim: To develop greater understanding of electronics through activities, crafts and games. Taken from the BB Company Section Discoverer Pro Pack, Skills Interests I2
• 1 metre of copper wire (or other conducting bare wire)
• 1/2 metre insulated wire
• 9v battery
• Lamp and/or small buzzer
• Ballpoint pen
• Wire cutters
• Electrical Components’ template
• Steady Hand Diagram’ template
• Citrus fruit (lemons or limes work best)
• 1 copper screw about 5cm long
• 1 zinc screw about 5cm long
• 1 bulb with 5cm leads
• Wire cutters
• 12cm square of balsa wood
• Two pieces of insulated copper
• Wire 20cm each
• 9cm x 5cm piece of cardboard
• Small compass
• Enough un-insulated copper wire to wrap around compass 15-20 times
• Two alligator clips
• Two paper clips
• Two screws with washers
• Various batteries any size
• Battery Tester’ template
Activity 1 - Steady Hand Game
Aim: Build a game that lets you test how steady your hand Is, by moving a loop around a wire figure without touching the wire. This makes a fun activity, and demonstrates the fact that current can only flow if there Is a closed circuit.
Cut up the Electrical Components template. Ask the group if they know what each sign is. If they are struggling give the group the cut up names and ask them to match the components to their names.
Steady Hand Game:
Distribute the Steady Hand Diagram template and instruct the young people to;
• Use the ballpoint pen to poke three holes in the lid of the shoebox, as shown.
• Snip off about 2cm of the insulated wire and put it aside for later.
• Bare both ends of the remaining wire.
• Make a small loop out of a short piece of the copper wire, and twist it onto one end of the insulated wire. Seal the join with tape to make a handle for the game.
• The size of the loop will determine how easy or difficult it is to win the game; the smaller the loop, the harder it is to win. You can modify the size of the loop later if it proves to be the wrong size.
• Pass the wire through the single front hole in the box lid.
• Transform the remaining copper wire into a series of bends. Make sure that the bends aren’t too close together, and that they don’t touch. Make as many bends as you want. (The more bends there are, the harder the game is to win.)
• Pass the loop handle you made earlier onto the wire with the bends, and Then insert the ends of this wire into the remaining two holes in the lid.
• Turn the lid over and tape down the end of the wire.
• Make a hole in the left front side of the box and insert the light bulb, as shown. Place the 9v battery in the box.
Note: The game is much more fun if you can find a buzzer to replace or in addition to the light bulb.
Tell the group that in order for the game to work, electricity must flow from one terminal of the battery, in a closed path (called a circuit), back to the other terminal.
• Attach one end of the wire to the bulb; twist it on tight and use tape to hold it.
• Use the short piece of insulated wire we cut off at the start, bare both ends, and attach it to the bulb socket tip, and one battery terminal. (Use tape to attach it to the socket tip: if you know how to use a soldering iron, a little solder will hold it permanently in place).
• Finally, attach the other end of the wire (this is the insulated wire with the loop) to the other battery terminal.
Now the game is ready to play. The object is to move the loop around the bends in the wire shape, from one end to the other, without letting the loop touch the wire. if the loop is very small, this can be very difficult to do! You’ll know when you lose, because the light bulb (or the buzzer) will come on! When this happens, it means the wire has made a complete circuit and you need to return to the beginning.
Ask the group:
What do you need to make a circuit?
In order for a circuit to work it is necessary to have an energy source, some conducting wires and an electrical device.
What is a circuit?
Electrical current happens when all the electrons move in the same direction. In a wire this would create a flow of electrons, like a flow of water. The electrons are already in the wire, but to make them move in the same direction they need a push. The battery provides the push the electrons need. Making a circuit means that there are no leaks or breaks, but there also needs to be a power supply which is the battery and this acts as a pump to send the water around. Consequently the electrons can carry energy all the way around the circuit.
Tips / Advice:
• Go to Maplin to get your electrical components http:/,.maplin.co.uk
• For some more really good inexpensive kits including a motorised glider, solar fountain, electrical noughts and crosses game, a radio, hovercraft, as well as ideas for wood work including a lantern, a woodpecker door knocker, a sand yacht and rockets then go to www.opitec.co.uk. You can also get components here as well. It’s really worth a Look!!
Activity 2 - Lemon Light
Aim: To light a lamp using only fruit.
Tell the group that your laboratory is running out of electricity and has asked you to help find a temporary source of energy to get a single light to help them work. Remind the group that a battery is nothing more than a device that stores metals and chemicals.
1. Roll the fruit under the palm of your hand to soften but don’t break the skin. Work it gently on a piece of scrap paper or a paper towel.
2. Insert the screws into the fruit about 5cm apart. Don’t allow the screws to go through the bottom of
3. Using wire cutters carefully remove about 1cm of the insulation from the leads connected to the lamp. Do not cut into the wire beneath the insulation.
4. Twist one end of the wire around one screw and the other end around the other screw.
5. If the bulb does not light try adding more lemons in a series circuit. If it does light what effect does adding another lemon have on the bulb.
6. Try using different fruits to make electricity. Ask the group why one fruit might work better than another.
Activity 3 - Battery Tester
Instruct your young people to:
1. Cut a piece of cardboard in the shape below using the ‘Battery Tester’ template.
2. Place the compass on the cardboard as shown. Using the un-insulated copper wire, lash compass to the cardboard 15-20 times, leaving 5cm of wire on each end.
3. Screw one of the screws in a corner of the balsa wood. Screw the second screw in the corner diagonally opposite. Attach washers to the back of the screws to hold them in place.
4. On a flat surface, place the compass face up on the balsa wood.
5. Attach one end of the copper wire that is wrapped around the compass to the top screw, and then attach the other end to the bottom screw.
6. Strip 5cm of insulation from each end of the two insulated copper wires.
7. Attach one end of one of the insulated wires to an alligator clip and the other end to the paper clip.
8. Repeat with the other insulated wire, alligator clip, and paper clip.
9. To test the battery, place paper clips on the positive and negative terminals of the battery, and then clip alligator clips to the screws on battery tester.
10. Note the movement of the compass needle.
11. Continue to test other batteries, and compare the amount of movement for each.
Ask the group:
1. How much of a difference was there In compass needle movement between batteries?
2. Why was there a difference? What are some factors that could cause a difference?
Some batteries may have been creating a stronger electrical current. Other factors might include the number of times the wire is wrapped around the compass, the type of battery tested, temperature, or the age of the battery.
3. Why does the compass needle move?
The compass needle moves because of the magnetic field created by the flowing current through the wire wrapped around the compass.
4. Why was It necessary to wrap the copper wire around the compass?
It was necessary to wrap the wire around the compass to create a magnetic field strong enough to move the needle. The more wraps of copper wire around the compass, the more sensitive the battery tester.
Tips / Advice:
• You could try making a casing for the batter tester out of a cardboard box. Find a way to attach the paper clips on the outside of the box.
• You could also replace the compass with, or add to the circuit, a light bulb.
For full details and diagrams see the BB Company Section Discoverer Pro Pack, Skills Interests I2